nor-

nor-, prefix Organic Chem.
  (nɔː(r))
  [f. normal a. and n.]
  1. a. Prefixed to the names of organic compounds to denote the replacement of one or (esp. in terpenes) all the (methyl) side-chains by hydrogen atoms.
  The use arose from the designation of a compound C₈H₆O₅ as ‘normal opianic acid’, of which opianic acid was supposed to be a dimethyl derivative: 1868 Matthieson & Foster in Jrnl. Chem. Soc. XXI. 358 We therefore propose to call the compound C₉H₈O₅ monomethyl-normal opianic acid, or if the contraction is admissible, methylnoropianic acid.
  norˈbornane [bornane f. borneol + -ane], the crystalline bicyclic hydrocarbon, C₇H₁₂, which is obtained by replacing the three methyl groups of bornane (camphane) by hydrogen atoms and is the parent compound of a number of terpenes; bicyclo[2.2.1]heptane; nordiˌhydroguaiaˈretic acid [f. guaiaretic acid, f. guaiac + Gr. ῥητ-ίνη resin of the pine], a crystalline phenol, C₁₈H₁₈(OH)₄, which is used as an antoxidant for oils and fats; noˈrephedrine, the crystalline, optically active compound, C₉H₁₃NO, which is obtained by replacing the methylamino group of ephedrine by an amino group and has actions and uses resembling those of ephedrine; noreˈthisterone, a crystalline compound, C₂₀H₂₆O₂, which has actions similar to those of progesterone and is used as a contraceptive and in the treatment of amenorrhœa and functional uterine bleeding; (β-)norˈnicotine [a. F. nornicotine (M. & M. Polonovski 1927, in Compt. Rend. CLXXXIV. 1333)], an optically active liquid alkaloid, C₉H₁₂N₂, found with and resembling nicotine; norsyˈnephrin(e = octopamine; norteˈstosterone, the 19-norsteroid derived from testosterone.

1952 Chem. & Engin. News 3 Mar. 930/3 Corresponding to these six types [of bicyclic compounds] are the four-parent ring systems northujane.., norcarane.., norpinane..and norbornane. 1962 E. L. Eliel Stereochem. Carbon Compounds x. 302 Norbornane, despite its easy accessibility, is an appreciably strained system. 1974 Jrnl. Chem. Soc.: Perkin Trans. II 322 (heading) Inhibition of ring expansion reactions in the norbornane system by neighbouring methyl groups.

[1919 Chem. Abstr. XIII. 991 Schiff's norguaiaretic acid is shown to be norhydroguaiaretic acid.] 1944 Oil & Soap XXI. 33/1 An investigation was made of the antioxydant properties of nordihydroguaiaretic acid. 1945 Jrnl. Amer. Pharm. Assoc. (Sci. Ed.) XXXIV. 81/1 One, if not the most active, of the bactericidal agents present in [the shrub] Larrea divaricata Cav. has been characterized as nordihydroguaiaretic acid. 1956 M. K. Schwitzer Margarine & Other Food Fats viii. 323 Nordihydroguaiaretic acid..was permitted to be used in the United States in December, 1943 at the rate of 0·01 per cent. The antioxidant effect is very marked in animal fats... It is less effective in vegetable fats. 1971 P. Tooley Fats, Oils & Waxes iv. 125 Oxidation can cause serious deterioration in a lipstick producing unpleasant rancid odours and taste... This can be largely prevented by the use of antioxidants such as..nordihydroguaiaretic acid.

1929 Chem. Abstr. XXIII. 2431 Reduction of PhCH(OH)CH(NO2)Me with Zn dust and dil. H2SO4 gave norephedrine..and nor-ψ-ephedrine. 1943 Jrnl. Lab. & Clin. Med. XXVIII. 704 Norephedrine and pseudonorephedrine together constitute propadrine, of which the commercial preparation contains also a small amount of ammonium chloride. 1973 Biochem. Jrnl. CXXXVI. 769/1 Norephedrine is extensively metabolized in the rabbit but not in man.

1956 Proc. Soc. Exper. Biol. & Med. XCI. 419/2, 10 mg nor-ethisterone given twice daily represents a reproducibly effective dose in women for the production of marked progestational changes. 1964 Norethisterone [see ethinylœstradiol]. 1973 Nature 10 Aug. 351/1 If inferences can be drawn from this preliminary study using mouse foetal hearts, it would seem that the concentration of norethisterone acetate in the pill should be kept to a minimum.

1927 Chem. Abstr. XXI. 3905 (heading) β-Pyridyl-α-pyrrolidine (nornicotine). 1936 Jrnl. Econ. Entomol. XXIX. 854 Macht & Davis..observed that β-nornicotine was more toxic for certain vertebrates..than natural nicotine. 1951 A. Grollman Pharmacol. & Therapeutics xv. 281 Nornicotine, which has similar actions to nicotine, lacks only the CH3 group in the pyrrolidine nucleus. 1968 Larson & Silvette Tobacco Suppl. I. 682/1 Nornicotine inhibited development of the chick-embryo, and was even more potent than nicotine in causing hydrops.

1952 Norsynephrine [see octopamine]. 1952 Ricerca Sci. XXII. 1576 Sympatho⁓mimetic amines (tyramine, norsynephrine, adrenaline, noradrenaline). 1960 Biochim. & Biophys. Acta XLIII. 568 The enzyme responsible for norsynephrin formation is dopamine β-oxidase.

1950 Jrnl. Chem. Soc. 367 This βγ-unsaturated ketone has now been isomerised..to the αβ-unsaturated ketone.., which is a 10-nortestosterone. 1955 H. Hirschmann Hormones III. xi. 544 19-Nortestosterone on the other hand, is inferior to testosterone as an androgen but equal to it in its myotrophic..effect. 1973 Jrnl. Appl. Physiol. XXXV. 378/2 Nortestosterone esters are more potent than testosterone in their capacity to stimulate erythropoietic activity in mice.

  b. Denoting the contraction of a chain or ring of carbon atoms by one methylene group, as norchoˈlanic acid [cholanic f. chol- + -an + -ic], a crystalline, optically active compound, C₂₃H₃₈O₂, obtained by shortening the side-chain of cholanic acid by one methylene group; norˈpinic acid, a crystalline dicarboxylic acid, C₈H₁₂O₄, existing in cis and trans isomers and differing from pinic acid in having a carboxyl group attached to the cyclobutane ring in place of a carboxymethyl group.

1927 Chem. Abstr. XXI. 590 Oxidation of I [sc. cholanic acid] by CrO3 in AcOH yielded the next lower homolog, norcholanic acid. 1958 C. W. Shoppee Chem. Steroids iv. 192 Similar reactions have been carried out in the norcholanic acid..series.

1909 Jrnl. Chem. Soc. XCV. 1170 Our experiments have, however, shown that this ring, in norpinic acid, exhibits quite unusual stability. 1932 J. L. Simonsen Terpenes II. iii. 129 By the action of dilute hydrochloric acid at 180° [on the cis-isomer], an equilibrium mixture of cis- and trans-norpinic acids is obtained. 1960 A. R. Pinder Chem. of Terpenes v. 91 The molecular formula and properties of norpinic acid suggested it was derived from cyclobutane.

  2. Denoting the normal (unbranched chain) isomer of the compound to whose name it is prefixed, as norˈleucine [ad. G. norleucin (E. Abderhalden et al. 1913, in Zeitschr. f. physiol. Chem. LXXXVI. 455)], an optically active, crystalline, non-essential amino-acid, CH₃(CH₂)₃CH(NH₂)COOH; norˈvaline [ad. G. norvalin (Abderhalden & Kürten 1921, in Fermentforschung IV. 328)], an optically active crystalline amino-acid, CH₃(CH₂)₂CH(NH₂)COOH.

1913 Jrnl. Chem. Soc. CIV. i. 1049 The acid, for which the name norleucine is proposed, has been combined with glycine and leucylglycine to form polypeptides. 1932 Jrnl. Biol. Chem. XCVII. 342 Norleucine has been isolated from spinal cord protein. 1961 D. M. Greenberg Metabolic Pathways II. xiv. 111 Norleucine is readily oxidized to CO2 in the intact animal. 1971 Nomencl. Org. Chem. (I.U.P.A.C.) (ed. 2) C. 42 193 (table) Norleucine..Norvaline. [Note] Use of ‘nor’ in these names to denote a ‘normal’ (unbranched) chain conflicts with more recent usage.

1921 Jrnl. Chem. Soc. CXX. i. 547 dl-α-Amino-n-valeric acid,..to which the name norvaline is given, is prepared by the usual methods from n-valeric acid. 1933 Ann. Rev. Biochem. II. 73 Further evidence of the occurrence of norvaline in proteins has been furnished by Abderhalden & Heyns..who report its occurrence in steer horn. 1969 Biochem. Jrnl. CXV. 621 Kinetic studies of glutamate dehydrogenase were made with wide concentration ranges of the coenzymes NAD+ and NADP+ and the substrates glutamate and norvaline.

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